After wading through an action-packed midseason finale Sunday which saw major characters introduced, other major characters killed off and maimed, as two of the show's most compelling guys face an angry mob of non-zombies, one thought nagged at the edge of my brain.

Does Walking Dead have a quota for the number of black characters who get to be on the show, especially if they're male?

I knew something was bugging me when I saw former prison inmate Oscar get gunned down, as hero Rick Grimes and his fellow survivors tried to rescue Maggie and Glenn from The Governor's tightly-run enclave, Woodbury. But there was so much action -- from sword-wielding Michonne taking out the governor's eye in a brutally physical fight to Grimes' survivalist second-in-command Darryl Dixon getting captured and vilified by Woodbury's resident with his psycho brother Merle -- that I paid little attention.

Until I looked on Twitter and saw my twinges of misgivings weren't just my own. Several folks wondered if the Walking Dead suddenly had a quota for characters of color, seeing Wire alum Chad Coleman join the show as Tyreese, leader of another group of scrappy survivors, in the same episode Oscar was killed.

Oscar began to come into his own as a character just as T-dog, an African American male character who had been on the show since its inception but had little impact, was killed. And its tough to talk about the Hispanic characters on the show, because there have been so few.

As I have written before, it is odd to see a show set in Georgia locations around Atlanta with so few black people anywhere. According to the last Census, Georgia is the state with the largest black population -- 30% of residents are African American. In Atlanta, 51% of the population is black people.

But there have rarely been more than two black characters of significance on the show at any one time; only in the last few episodes has any black character been featured enough to rival some of the other major characters on the show. I have written before about how the TV industry is wary of putting too many non-white characters on a show focused on a mainstream, mostly white audience.

In my book Race-Baiter, I recall how writers for HBO's The Wire such as David Simon and Dennis Lehane lamented that the series' audience seemed to peak when it had the most white characters on it. When the show was focused more on the all-black drug dealers and half black police force, interest dipped, they said. Black viewers have never been considered big fans of so-called genre shows such as science fiction and superheroes. (though, given how some characters of color are treated, is that surprise?)

But I'm not sure I buy that. If a TV writer or showrunner is bad at creating plot arcs or sucks at dialog, no one sits back and accepts such drawbacks. Producers, TV executives and critics push those people to make good shows better; sometimes it works and often it doesn't.

The only difference here is that a lack of diversity typically doesn't bother TV audiences unless the omissions are glaring and complete.

I bring this up mostly in hopes of helping to create a conversation which reaches the producers of the Walking Dead. As last night's midseason finale ended, there were three black characters on the show, two of whom were prominently featured in the graphic novel which inspired the show, Tyreese and Michonne.

Given all the storylines laid out in this last episode -- a murderous Governor ready to exact revenge on Grimes and his group, Michonne still in an uneasy alliance with Grimes and his folks, Tyreese and his people locked in a cell at the prison where Grimes and his group are living and survivalist brothers Merle and Darryl facing a raving crowd together at Woodbury -- there's no need to cut down on the show's diversity just yet. When the show returns in February 2013, I'm hopeful we'll see a more diverse group of survivors hanging on by their fingernails at the edge of civilization.

It may seem odd to spend this much time thinking about racial dynamics in a show based on a zombie apocalypse. But these programs are always allegories for deeper messages -- and often they succeed by making as many elements of the show realistic as possible, so when the crazy stuff happens, you believe it more.

And let's be honest, on a supercool show which is capturing TV fans' passion, it only makes sense that people of color would want to get in on the party, too.